I got this from a post on usenet. I thought it useful. It did make
me wonder if this DM had problems of his own, though.

We've all played with some good and bad gamers. Which FIVE
of the following fifteen player-types do you hate to game
with the most?

Munchkin. Loves to brag that his character will 'win the
game.' Wants to have the perfect combination of magic items
and high levels so that he can feel, in his own mind, that
everyone else thinks he's the greatest character on the
planet. After he get's the perfect combination, he rubs it
in the DM's face, securing his future. He hopes that by
irritating the DM, he can be faced with 'the ultimate
challenge'..which he knows he'll win ironically easily.
Would play the psionist even more often, but he belives that
there aren't enough good magic items out there for him to
gain.

Min-maxer/Efficiency-fanatic-wargamer. Get's pissed off
at other players if they make an elf and don't take a long
sword and bow for the weapon bonus. Loves the players
option books, because he gets to min/max everything. Tend
to like to tell other players what to do, so that the
session runs more like a military operation, than a game.
Demands that the DM use spell points, character points, and
merit points. Never uses PC names. Usually says things
like, "Thief, go check the door for traps. Mage, cast a
fireball on 'that' battlemat square." Knows more about your character than you do, and assesses blame when something bad
happens to their character.

Notta' Role-Player. Cannot role-play to save his life so
he makes character backgrounds as, "Mysterious and quiet." He is so introverted that he rarely says a word unless
asked. Conjures a great game in his mind, but never shares
it with anyone, unless he blurts out some inane
pseudo-role-playing statement like, "my elven-fighter says, "grrr. I'm going to get you..you..orc." His idol is Silent Bob. Will oftentimes stare at everyone else, chuckling to
himself, as if he has some dreadful secret.

Vocal Rules Lawyer. Will argue with other players or the
DM if they feel that the rules might be violated in a way
that will affect him or his mission. It's OK for him to bend
the rules, but other players cannot. They also tend to make
up arbitrary 'false rules claims' if things aren't going
their way, just to make the DM make a hasity ruling on the
spot. If the rule has significant loopholes, he'll settle
his case momentarily and conveniently bring it up again
later with the saying,"but last time you ruled..[insert
twisted and false claim ruling here]." Enjoys arguing for
the sake of arguing, while forsaking the game and the other
players' time.

DM Antagonist. Always bored, because "I've been there,
done that." So you like to try to throw the DM by going in
deliberately antagonistic plot directions that gives the DM
a big headache. Always asks the DM to look stuff up for
him, usually during the peak situation of the game, because
"he can't find it in his book." Likes to cross over player knowledge with character knowledge by claiming that his
half-orc has created gunpowder, blinding powder, hand
grenades, gattling-spearguns, and complex feats of
engineering. Pouts when the DM disallows these things.

Lone wolf. Character player, who will often tend to sneak
away from the group to 'see if they can find a little extra
loot.' Other players and the DM are always pissed off
because he is wasting their limited gaming time (although he
doesn't realize it, because it's his god-given right to play
his thief that way.) Wants incredible details of his
move-silently actions or what he finds in the merchant's
pockets. Is still pissed off that experience is no longer
gained by defeating/sneaking by monsters and gaining
treasure.

Immature and petty whiner. Tends to do stupid or childish
things when the game isn't going their way. Will carry over
petty grudges with players or characters in different
campaigns. Will often do dumb things like start a wrestling
match with another player, or will unhesitantly punch the
Lord-Mayor of Greyhawk in the face if they get even the
slightest bit annoyed. If their character dies, they will
storm out of the room or sit and cry to the DM or other
players about how UNFAIR it was.

Mutinous and opportunistic prankster with malice and
aforethought. Likes to create problems for players just to
see other players fight or attempt to get out of tough
situations. Will, 'accidentally' fireball the theif if he
gets in the way. If no one else is paying attention, his
mage-thief steals the campaign-crucial, holy-avenger sword
from the tomb and sells it to an NPC. If he didn't start
that way, he'll work towards getting an evil alignment.
Tends to like to create characters that can do it all, but
will withhold all actions, just to see the party squirm,
then charge in to save the day.

Overbearing, extroverted, actor-wannabe. Personality that
talks too much, and usually in a really irritating accent.
He never lets anyone else speak. They think they have a lot
of great ideas and everyone needs to hear them. Can breathe
through his ears, which helps him chatter his jargon without
abandon. This person always wants to sit right next to the
DM or in a position that puts him where he can obstruct
action without much difficulty.

Lost and Confused Space Case. This person always forgets
their character and doesn't have any organizational skills
at all. They don't have a clue about the campaign, and are
often more interested in their computer games, or something
else not related to the game at hand. Other players take
advantage of him and trade him beads for his magic items.
Doesn't own a players handbook or dice. Lives with his
mom. Appears to be on some sort of illicit drug, but no
evidence can be unearthed. Say's "Dude" way too often. Likes to play a spellcaster and has to look up the
definition of magic missile and cure light wounds at least
twice per game.

Quitter. Tends to drop out of a lot of campaigns because
they, "Can't find the time." Really interested for the first 1-2 sessions and get's the DM and other characters to
spend an inordinate amount of time preparing a complex
character background for him, possibly with the campaign
revolving around something special about that character, but
then quits the game. Has probably tried to make his own game
because he doesn't like the AD&D rules. A subcategory of
this type of player is the Unreliable. This person shows up
1-2 hours late without warning, or not at all during crucial
gaming sessions, but still has most of the traits listed
above

Beuller..anyone..Beuller..Story Teller. Likes to talk
about inane statistical character or game details for
extended periods of valuable gaming time. Often times
considers self to be an expert at explaining military and
medieval details, especially in the long-sword versus
broad-sword debate. Also, tends to tell a lot of boring old
character stories, regardless of their relevance to the
current game. People just nod their heads when you speak to
them, unless you are speaking with another of your kind, at
which time the room clears out. Knows all of the
band-aid-justifications of the
out-of-date-Tolkien-based-AD&D-racial-systems, such as why
elves raised in a city, by human farmers are experts at
longswords, bows, and invisible movement in woods. Kicked
out of his philosopy class for casting sleep spells.

Automaton. This person is controlled by their wife or
another member of the group. Cannot think for themself. If
the wife or girlfriend is present at the game, he is always
in trouble. Spends a lot of time kissing ass to the
significant other. Probably likes to play, but always ends
up dropping out because of the inability to control ones own
life. A gimp. Has to ask others what to do.

Cheater. This player has never had a die roll less than 14
on a d20. They usually sit as far away from the DM as
possible. Puts all of his stuff on the table, so as to mask
as many rolls as possible. Uses a lot of practice dice
rolls or 'plops' them from less than 2" off the table.
Spins or stacks dice. This person wants to make a character
during the middle of the game session, during a combat,
because he knows the nobody can observe his rolls. If he is
a spellcaster, he will claim that he cant find the rule.
Carries large stacks of paper, so that the DM cannot
possibly see his entire spell list. Never writes anything
down. If the DM asks for his spell list, he claims that he
left that sheet at home.

Uptight Grump. This player is always cranky or tired.
People fear him because 'he don't like nobody touching his
stuff.' Has wrinkles from frowning and chalk marks from
dried sweat. Swears, breaks pencils, and throws dice when
things don't go his way. Makes his own diamond dice
'internally,' using coal. Most of his character sheets are
crumpled up, and books are in serious need of repair. Sits
near the pencil sharpener (which scares people more).
Drinks Surge, Mountain Dew, and Double Espresso and eats
food that complicates the situation. Smells bad. Usually
plays a horribly complex character.